And tempering glass



(No Mom.)

J. H. CAMPBELL.

METHOD 0D AND APPARATUS DOR ANNEALING AND. TBMPDDINGGLASS. No. 254,272. N 8,1882.

UNITED STATES PATENT OFFICE.-

JOSEPH H. CAMPBELL, OF NEW, YORK, N. Y., ASSIGNOR OF ONE-FOURTH TO JAMES MCLAIN, OF WASHINGTON, I). O.

MEIHOD F AND APPARATUS FOR ANNEALING AND T'EMPERING GLASS.

SPECIFICATION forming part of Letters Patent No. 254,272, dated February 28, 1882.

Application filed January 23, 1882. (No model.)

To all whom t may conce-rn Beit known that I, JosEPH H. CAMPBELL, a citizen ofthe United States, residing at New York city, in the county of NewYork and State of -New York, haveinvented certain new and useful Improvements in the Method of and Apparatus forAnnealin g or Tempering Glass, Src.; and I do declare the following is a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to the letters and figures of reference marked thereon, which form a p art of this specication.

Myinvention relates to the method of and apparatus for annealing and tempering glass, Ste. My invention consists in submitting glass and other articles to be annealed and tempered to the action of heated gases in motion until the proper degree of heat has been attained, whereby the crystals are formed or arranged in the line or direction of the traveling cu rrents ofthe heated gases.

My invention consists, further, in submittin g glass and other articles to be annealed or tempered to the action of heated gases in motion until the proper degree of heat has been attained, and then to the action of the same gases under a regulated pressure until the desired molecular rearrangement, crystallization, or polarization has taken place, and finally cooling such articles by subjecting them to the action of carbonio-acid gas and nitrogen gas.

My invention consists, further, in certain devices or apparatus, hereinafter more fully set forth for the accomplishment or carrying out of the annealing or tempering process.

The drawing hereunto annexed is a vertical lon gitudinal'sectional view of my apparatus or plant.

The improvement I propose to effect in the art of annealing and tempering is accomplished by heatin g the articles to be treated in achamber by heated gas, which acts on them chemicallyduriug theproce'ss of heatin g, or that heats them in part by its chemical action, and having obtained the required annealing or tempering heat to maintain that very heat for a time sufficiently long to secure the desired results; also, by having, during the cooling process, all

. articles which expand when passing from the liquid to the solid state under a pressure of gas greater or less than the atmospheric pressure, according to the crystallization that may be desired or required, and all that contract when passing from the liquid to the solid state in a mechanical vacuum. Carbonio-oxide gas diluted with an admixture of from. fty to seventy-live per cent. of nitrogen gas is used as the heating agent, and for cooling purposes carbonio-acid gas and nitrogen are employed. The cooling is not eected by radiation or conduction, but by convection, and therefore subofcombustion from the furnace to the annealing-chamber A. The pipes O C are rigidly attach ed to the sides ofthe ash-pit B and extend down-to within one inch of thetop of the chamber A.

O C are telescopic collars, by which connection is made between the pipes C C and chamber A. The space between the ends of the pipes C C andchamberA, when the collars are raised, is intended to admit of suitable covers orlids to prevent the escape of the gases Where there is a pressure in the chamber A, and are kept in their place by the weight of the collars (5 O or other suit-able device resting thereon.

E is a pressure-blower, such as the Root blower, having the properties of an air-pump as well as that of a blower, located in the pipe K, as shown, which connects the annealing or tempering chamber A with the gasometer H for the purpose of effecting a downdraft Y IOO gases until they are required to carry off the heat and lower the temperature of the chamber A and the articles contained therein.

K is a pipe leading from the bottom of the chamber A to the gasometer H for the purpose of conducting the gases which have been drawn from the furnace B through the cham ber A to the gasometer H.

K K are two valves located in the pipe K, on each side of the blower or pump E, the object and purpose of which will be hereinafter explained. y l

Lis a pipe provided with a valve, Z, to relieve the pressure of the gases in the gasometer H.

L is a pipe connecting the gasometer H with the chamber A, for the purpose of conveying the cooling-gases to chamber A, and is provided with a regulating-valve to control the flow of gas.

M M are valves located in the sides of the chamber A to permit the gases to escape in the cooling process.

D is a pipe leading from the ash-pit B down to a point between the chamberA and blower or pump E, where it is connected to the pipe K.

D is a'pipe leading from the pipe K at a point between the blower or pump E and gasometer H to chamber A. The pipes D Dl are for the purpose of forcing heated carbonio-oxide gas and nitrogen into the chamberA to produce a pressure therein, and are provided with valves T Tll T" T, which are closed when pressure is not required in the chamber A.

The articles to be annealed or tempered are placed in the chamber A, and the furnace B charged to a depth of twenty or twenty-five inches with charcoal. A fire is lighted on top of the furnace, or rather on the top of the pile 4or charge of charcoal, and by the aid of the blower or pump E a strong downward draft is produced. In the act of combustion the oxygen of the atmosphere, uniting with the carbon, produces carbonio-acid gas, which, being drawn down through the burning charcoal, is converted into carbonic-oxide gas, and, with the heated nitrogen, drawn through the chamber A, where they perform the ofiice of annealing, and are then conducted through the pipe K and forced into the gasometer H. By continuing this operation for a time the chamber A and its contents are heated to the requisite temperature for tempering and annealing, which is from 3000 to 6000 Fahrenheit, depending on the article to be annealed or tempered.

If glass or other articles which expand in passing from the liquid to the solid stateare to be treated, break the connection between the furnace B and the chamber A by lifting the collars C C and closing the openings with suitable covers, which will be kept in place by the weight of collars C C', and close the valves K K", thus closing all the openings in chamber A. The valves T T T" T" in the pipes D and D are now opened, and the pump or blower started. This operation will force the gases of combustion into the chamber A, and maintain therein the desired temperature and pressure during the period of time required for the treatment or soak of the articles. To cool the chamber Aland its contents, close the valves T T T" T" in the pipes D and D', open the valves K and K in pipe K,and open valve L in pipe L. This operation permits the cooling-gases retained in gasometer H to pass to chamber A. The carbonio-oxide gas which was forced into the gasometer has been converted into carbonio-acid gas by the free oxygen of the air contained in the water. If rapid cooling is required, open the valves M M in chamber A.

If articles are to be annealed which contract in passing from the liquid to the solid state, no use is made of the pipesDD. Simply make the connection between the chamber A and the furnace B by attaching the pipes C C, and continue to run the blower or pump. The cooling of this last-mentioned class of articles is the same as before described.

Inasmuch as in passing the heated gases through the chamber the atoms or molecules of certain articles to be treated are polarized or arranged ina line' or direction of the said gases by reason of the electro-chemical action of said gases, it is preferable in the cooling process that the gases be discharged in the same direction as that in which they passed in the heating process.

I am aware that it has been proposed to anneal glass by reheating the same by direct exposure to highly-heated gases which are under pressure, and then gradually cooling the same together with and within the furnace.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, 1s

l. The method herein described of annealing and tempering glass and other articles, the same consisting in subjecting such articles to the action of gases heated and in motion, whereby the crystals are formed or are arranged in the'line of direction of the traveling currents of the heated gases, as set forth.

2. The method herein described of annealing and tempering glass, Ste., the same consistin g in submittin g the articles to be annealed or tempered to the action of heated gases in motion until the proper degree of heat has been attained, and then to the action of said heated gases under regulated pressure until the desired molecular rearrangement, crystallization, or polarization has taken place, and finally cooling such articles by subjecting them to the action of carbonic-acid gas and nitrogen gas, as set forth.

3. The method herein described ofannealing and tempering glass, &c.,the same consisting in submitting the articles to be annealed or tempered to the action of heated carbonic gxidle gas and nitrogen gas in motion, as set ort IOO

TIO

IIS

4. The method herein described of annealing and; tempering glass, &c'., the same consisting in generating the gases for annealing or tempering the articles in a furnace, substantially such as described, and conveying the same direct in a heated condition to the annealingv or tempering chamber, as set forth.

5.- The furnace B, ash-pit B', pipes C, and

' sleeves C', in combination with the chamber A,

7. The gasometer H, pipe L, and valve L', in combination with the annealing or tempering chamber A and pipes M M, whereby the cooling-gases from the gasometer are admitted to the annealing or tempering chamber and the articles cooled rapidly or slowly, as may be desired. s

S. The method herein described of cooling annealed or tempered articles by convection, u

as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

JOSEPH H. CAMPBELL.

Witnesses:

T. C. BRECHT, A. H. BETZ. 

